Peri-implantitis is an infectious disease that affects about one of five patients who receive a dental implant within 5 years after the surgery. To minimize this reaction the development of new biomaterials with antibacterial action is needed that can be used as a coating material in orthodontic implants. In addition, these biomaterials can be doped with several ions, which add specific properties that may act at the cellular level, such as increasing the angiogenesis efficiency. In this work, 45S5 Bioglass® has been used as the base material because it presents higher bioactivity compared to other biomaterials. To add antibacterial function and increase positive effects on bone metabolism, zinc and magnesium ions were introduced in the glass network. The main objective was the synthesis of the 45S5 glass by melt-quenching and study the biological performance as function of the zinc and magnesium concentrations. The structural and biological properties of the prepared samples are discussed.

High Strength Concrete (HSC) slab–column connections with relatively low concrete strengths compared to today’s capabilities have been tested under seismic-type loading in the past. Herein, the hybrid use of HSC with compressive strength around 120 MPa and Normal Strength Concrete (NSC) is investigated through three reversed horizontal cyclic loading tests with different geometries of the HSC region and a reference NSC specimen. The results show that HSC applied in the vicinity of the column can significantly enhance the seismic performance of slab–column connections. The best result in terms of drift capacity and economic use of HSC was achieved in the case of full-depth HSC extended from the column’s face up to 2.5 times the effective depth. Drift ratios up to 3.0% were achieved. A comparison with previous tests showed that the hybrid use of HSC and NSC can achieve similar results to the provision of punching shear reinforcement.

Composites are finding increased use in structural high demanding and high added value applications in advanced industries. A wide diversity exists in terms of matrix type, which can be either polymeric or metallic and type of reinforcements (ceramic, polymeric or metallic). Several technologies have been used to produce these composites; among them, additive manufacturing (AM) is currently being applied. In structural applications, the presence of defects due to fabrication is of major concern, since it affects the performance of a component with negative impact, which can affect, ultimately, human lives. Thus, the detection of defects is highly important, not only surface defects but also barely visible defects. This chapter describes the main types of defects expected in composites produced by AM. The fundamentals of different non-destructive testing (NDT) techniques are briefly discussed, as well as the state of the art of numerical simulation for several NDT techniques. A multiparametric and customized inspection system was developed based on the combination of innovative techniques in modelling and testing. Experimental validation with eddy currents, ultrasounds, X-ray and thermography is presented and analysed, as well as integration of distinctive techniques and 3D scanning characterization.

Fast, real-time detection of gases and volatile organic compounds (VOCs) is
an emerging research field relevant to most aspects of modern society, from
households to health facilities, industrial units, and military environments.
Sensor features such as high sensitivity, selectivity, fast response, and low
energy consumption are essential. Liquid crystal (LC)-based sensors fulfill
these requirements due to their chemical diversity, inherent self-assembly
potential, and reversible molecular order, resulting in tunable stimuliresponsive soft materials. Sensing platforms utilizing thermotropic uniaxial
systems—nematic and smectic—that exploit not only interfacial phenomena,
but also changes in the LC bulk, are demonstrated. Special focus is given to
the different interaction mechanisms and tuned selectivity toward gas and
VOC analytes. Furthermore, the different experimental methods used to
transduce the presence of chemical analytes into macroscopic signals are discussed and detailed examples are provided. Future perspectives and trends
in the field, in particular the opportunities for LC-based advanced materials in
artificial olfaction, are also discussed.

The fast and non-invasive detection of odors and volatile organic compounds (VOCs) by gas sensors and electronic
noses is a growing field of interest, mostly due to a large scope of potential applications. Additional drivers for the
expansion of the field include the development of alternative and sustainable sensing materials. The discovery
that isolated cross-linked polymeric structures of suberin spontaneously self-assemble as a film inspired us to
develop new sensing composite materials consisting of suberin and a liquid crystal (LC). Due to their stimuliresponsive and optically active nature, liquid crystals are interesting probes in gas sensing. Herein, we report
the isolation and the chemical characterization of two suberin types (from cork and from potato peels) resorting to
analyses of gas chromatography–mass spectrometry (GC-MS), solution nuclear magnetic resonance (NMR), and Xray photoelectron spectroscopy (XPS). The collected data highlighted their compositional and structural differences. Cork suberin showed a higher proportion of longer aliphatic constituents and is more esterified than potato
suberin. Accordingly, when casted it formed films with larger surface irregularities and a higher C/O ratio. When
either type of suberin was combined with the liquid crystal 5CB, the ensuing hybrid materials showed distinctive
morphological and sensing properties towards a set of 12 VOCs (comprising heptane, hexane, chloroform,
toluene, dichlormethane, diethylether, ethyl acetate, acetonitrile, acetone, ethanol, methanol, and acetic acid).
The optical responses generated by the materials are reversible and reproducible, showing stability for 3 weeks.
The individual VOC-sensing responses of the two hybrid materials are discussed taking as basis the chemistry of
each suberin type. A support vector machines (SVM) algorithm based on the features of the optical responses was
implemented to assess the VOC identification ability of the materials, revealing that the two distinct suberin-based
sensors complement each other, since they selectively identify distinct VOCs or VOC groups. It is expected that
such new environmentally-friendly gas sensing materials derived from natural diversity can be combined in arrays
to enlarge selectivity and sensing capacity.

Eco-sustainable and recyclable porous carbons are reported as metal-free catalysts for the synthesis of benzodiazepines for the first time. The porous carbons were able to efficiently catalyse the synthesis of benzodiazepine 1 from o-phenylendiamine 2 and acetone 3 under mild conditions. Both acidic functions and the porosity of the catalysts were determinant features. High conversion values were obtained when using HNO3 oxidized carbons. The highest selectivity to benzodiazepine 1 was obtained in the presence of the most microporous catalyst N-N, which is indicative of the great influence of porous properties. Stronger acid sites and high microporosity of the carbon treated with H2SO4 yield benzodiazepine 1 with total selectivity.

Chromium is one of the most important raw materials for the European Union. Adsorption has become an important process for the recovery of metals from wastewaters, which has led to a demand for low-cost and eco-friendly adsorbents. The objective of this work was to use new and renewable carbon-based adsorbents from rice wastes in the removal/recovery of Cr(III) from synthetic and real wastewaters. Rice wastes were submitted to co-pyrolysis and the resulting char was optimized through physical and/or chemical activations/treatments. A commercial activated carbon was used for comparison purposes. All adsorbents were characterized (including an ecotoxicity test for the char precursor) and submitted to Cr(III) removal assays from a synthetic solution, in which two solid/liquid ratios (S/L) were tested (5 and 10 g/L). The CO2 activated carbon at a S/L = 5 g/L was the biomass-derived adsorbent that performed better, obtaining a maximum Cr(III) uptake capacity of 9.23 mg/g comparable to the one obtained by the commercial adsorbent at the same S/L (9.80 mg/g). The good results on this biomass-derived carbon were due to the effective volatile matter removal during the activation (from 22.7 to 4.25% w/w), which increased both surface area (from <5.0 to 325 m2/g) and ash content (from 30.0 to 40.4% w/w), allowing an increase in Cr(III) removal due to ion exchange mechanism and porosity development. The best adsorbent, under optimized conditions, was also applied to a chromium rich industrial wastewater. The results obtained in this real case application demonstrated a competition effect due to the presence of other ions.

Background The awareness of environmental and socio-economic impacts caused by greenhouse gas emissions from the livestock sector leverages the adoption of strategies to counteract it. Feed supplements can play an important role in the reduction of the main greenhouse gas produced by ruminants—methane (CH\textsubscript{4}). In this context, this study aims to assess the effect of two biochar sources and inclusion levels on rumen fermentation parameters \textit{in vitro}. Methods Two sources of biochar (agro-forestry residues, AFB, and potato peel, PPB) were added at two levels (5 and 10%, dry matter (DM) basis) to two basal substrates (haylage and corn silage) and incubated 24-h with rumen inocula to assess the effects on CH\textsubscript{4} production and main rumen fermentation parameters \textit{in vitro}. Results AFB and PPB were obtained at different carbonization conditions resulting in different apparent surface areas, ash content, pH at the point of zero charge (pHpzc), and elemental analysis. Relative to control (0% biochar), biochar supplementation kept unaffected total gas production and yield (mL and mL/g DM, \textit{p} = 0.140 and \textit{p} = 0.240, respectively) and fermentation pH (\textit{p} = 0.666), increased CH\textsubscript{4}production and yield (mL and mL/g DM, respectively, \textit{p} = 0.001) and ammonia-N (NH\textsubscript{3}-N, \textit{p} = 0.040), and decreased total volatile fatty acids (VFA) production (\textit{p} < 0.001) and H\textsubscript{2} generated and consumed (\textit{p} ≤ 0.001). Biochar sources and inclusion levels had no negative effect on most of the fermentation parameters and efficiency. Acetic:propionic acid ratio (\textit{p} = 0.048) and H\textsubscript{2} consumed (\textit{p} = 0.019) were lower with AFB inclusion when compared to PPB. Biochar inclusion at 10% reduced H\textsubscript{2} consumed (\textit{p} < 0.001) and tended to reduce total gas production (\textit{p} = 0.055). Total VFA production (\textit{p} = 0.019), acetic acid proportion (\textit{p} = 0.011) and H\textsubscript{2} generated (\textit{p} = 0.048) were the lowest with AFB supplemented at 10%, no differences being observed among the other treatments. The basal substrate affected most fermentation parameters independently of biochar source and level used. Discussion Biochar supplementation increased NH\textsubscript{3}-N content, \textit{iso}-butyric, \textit{iso}-valeric and valeric acid proportions, and decreased VFA production suggesting a reduced energy supply for microbial growth, higher proteolysis and deamination of substrate N, and a decrease of NH\textsubscript{3}-N incorporation into microbial protein. No interaction was found between substrate and biochar source or level on any of the parameters measured. Although AFB and PPB had different textural and compositional characteristics, their effects on the rumen fermentation parameters were similar, the only observed effects being due to AFB included at 10%. Biochar supplementation promoted CH\textsubscript{4} production regardless of the source and inclusion level, suggesting that there may be other effects beyond biomass and temperature of production of biochar, highlighting the need to consider other characteristics to better identify the mechanism by which biochar may influence CH\textsubscript{4} production.